GM's 230 mpg Chevy Volt aka Toyota Prius killer

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exerpts from the article:

General Motors Corp. said Tuesday its Chevrolet Volt rechargeable electric car should get 230 miles per gallon of gasoline in city driving, more than four times the current champion, the Toyota Prius.

Henderson said charging the volt will cost about 40 cents a day, at approximately 5 cents per kilowatt hour.

Most automakers are working similar plug-in designs, but GM could be the leader with the Volt, which is due in showrooms late in 2010.

Toyota’s Prius, the most efficient car now sold in the U.S., gets 48 miles per gallon (20 kilometers per liter) of gas. It is a gas-electric hybrid that runs on a small internal combustion engine assisted by a battery-powered electric motor to save gasoline.

Although Henderson would not give details on pricing, the first-generation Volt is expected to cost near $40,000, making it cost-prohibitive to many people even if gasoline returns to $4 per gallon.

The price is expected to drop with future generations of the Volt, but GM has said government tax credits of up to $7,500 and the savings on fuel could make it cost-effective, especially at 230 miles per gallon.

full article here:
http://www.msnbc.msn.com/id/32370233/ns/business-autos?GT1=43001
 
These numbers are total [censored]. They are saying if you drive it 40 miles on a battery then a few miles on gas that works out to a 240 MPG rate. Baloney.

The MPG rate should be based upon how much fuel it uses WHILE IT IS RUNNING ON GAS. If this is how they figure the numbers, why not say you can drive it 40 miles on a battery, then 2 inches on gas and have a 10,000 MPG rate? It's all nonsense.

Read more here:
http://www.thetruthaboutcars.com/volt-birth-watch-155-the-230-mpg-alleged-game-changer/

John
 
Originally Posted By: Tosh
Who gets electricity for 5 cents/kWh? The national average is 12 cents/kWh...


I am paying 10 cents per kWh here in Northern Wisconsin with Excel energy.
 
This simply illustrates the need for a new way to measure energy consumption instead of mpg. If you charge the Volt overnight and always drive less than 40 miles per day, you would never need any gas and your mpg would be infinite. But obviously it's consuming energy.

That said, I am very skeptical that someone driving 40 miles per day will only pay $0.40 per day to charge it.
 
Originally Posted By: John_K
The MPG rate should be based upon how much fuel it uses WHILE IT IS RUNNING ON GAS. If this is how they figure the numbers, why not say you can drive it 40 miles on a battery, then 2 inches on gas and have a 10,000 MPG rate? It's all nonsense.

Agree. An MPG rate should be applicable regardless of how many miles you drive. You can't have an MPG rate that only applies to the first 40 or 50 or whatever miles, and then have a completely different MPG rate for the remaining distance driven.

Using an MPG rate for an electric vehicle is silly, IMO. We need a different way to measure the fuel economy here, since in some cases the fuel is no longer gasoline and is not expressed in gallons.
 
While I do not doubt that it is highly efficient, I do not buy those numbers.

Figure it this way:

What is the round trip efficiency of a decent battery/power electronics set? ~93% storage to AC out, 85% AC in to stored energy.
What is the efficiency of a fuel-powered electric cogen plant? ~40%
Compared to a theoretical IC only setup in, say a prius or Ford fusion, what is the "benefit" of electric drive and regenerative braking? Ill use the fusion as it is the most apples to apples... it is 39 combined on the hybrid, 25 combined on the 2.5L gas. That is roughly a 50% benefit to using hybrid electric for traction.

So...

-Our gas-only traction is roughly 15% efficient fuel in to power out, which is roughly what an otto cycle engine will do.
-Our hybrid drive unit is roughly 15% + 50% of 15% = 22.5% efficient fuel in to power out.
-A battery-only device would be 93% of 40% generation / distribution efficiency, or 37.2% efficiency fuel in to power out.
-A battery-only system with regeneration would be 37.2% battery efficiency plus 85% of a 50% benefit of the operational efficiency... so let's just say 85% of 15% for a total of 49.9% efficent fuel in to power out.

So even if my electrical power generation and distribution number (I used 40%) is lower, it is still far ahead of anything else.

Now, where I think the math gets creative is if I say that a regenerating battery car is 49.9% efficient, vs a hybrid which is 22.5% efficient, then I might do some sloppy math and say that the battery car should go 49.9/22.5 = 2.21x further on the same quantity of energy provided due to efficiency...

But then how does one get 240MPG? I can see saying that the prius gets 48 MPG, so theoretically the volt gets 106MPG... but 240?!?!?!?
 
Originally Posted By: Lorenzo
This simply illustrates the need for a new way to measure energy consumption instead of mpg. If you charge the Volt overnight and always drive less than 40 miles per day, you would never need any gas and your mpg would be infinite. But obviously it's consuming energy.


Yes like energy units per mile or some such, or one for the electric mode and one for the gas mode, or something that has some basis in reality.

John
 
In the article it says the 230 mpg claim is using draft guidelines from the epa for vehicles like the volt.
 
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If it's anything like the GTR it will be smoke and mirrors with no one other than Nissan being able to get those numbers ...
wink.gif
 
I'll take any four cylinder family sedan with it's 35 mpg and 22 thousand dollars in the glove box instead.

Electricity in volume would be kilowatt hours.

It's a technological masterpiece I'm sure, but out of touch with the reality of the situation. People who want to save money on gas don't have 40,000 + to buy a car. People who do have that sort of cash don't care about saving money on gas. See the BMW 335d for another example. Sure a few will buy them for the cache, but that won't move the volume needed to recoup the development costs.
 
Originally Posted By: bepperb
I'll take any four cylinder family sedan with it's 35 mpg and 22 thousand dollars in the glove box instead.

Electricity in volume would be kilowatt hours.

It's a technological masterpiece I'm sure, but out of touch with the reality of the situation. People who want to save money on gas don't have 40,000 + to buy a car. People who do have that sort of cash don't care about saving money on gas. See the BMW 335d for another example. Sure a few will buy them for the cache, but that won't move the volume needed to recoup the development costs.


Well said and a great post. I'll take my $14K brand new 08 Corolla with a "measly" 35-40 mpg, pocket the $26K, and be a happy man!
 
Originally Posted By: bepperb
See the BMW 335d for another example. Sure a few will buy them for the cache, but that won't move the volume needed to recoup the development costs.

I don't really think that BMW counts on diesel sales in the US to recoup the development costs. Most of those costs will be recouped by sales in Europe where a diesel-powered BMW is not considered blasphemy and "unsporty".
 
For a lot of the driving I do, I might need to add STA-BIL to the gas with one.

I am paying about 10 cents a KWH including sales tax. I am not sure if they charge on a sliding scale. If so, I would do better.
 
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